OpenAI to Watermark ChatGPT Text in EU Under AI Act Rules

OpenAI will begin adding an invisible statistical watermark called textGrain to eligible ChatGPT and Codex text in the European Union to comply with the EU AI Act.

Article 50(2) of the EU AI Act requires generative AI providers to ensure AI-generated or manipulated content is marked in a machine-readable format.

OpenAI noted that edits significantly weaken the detection signal, reducing detection rates from about 92% to 17% when 25% of words are replaced with synonyms.